Drill motor collet mounts



June 24, 1958 R. T. HANGER 2,839,953

DRILL MOTOR COLLET MOUNTS Filed Oct. 24. 1955 2 Sheets-Sheet 1 l yJNVENToR. l PAA/00cm ryA/vage A Trae/M745 June 24, 1958 R. T. HANGER2,839,953

DRILL MOTOR COLLET MOUNTS Filed Oct. 24. 1955 2 Sheets-Sheet 2 ,4TORNEI/5' Www-WWK jig.

Airplane Company Seattle, Waslu, .a,.c0rporation of Delaware i v In worksuch as aircraft construction, motor-driven drills are usedbtoboreholeseinafzwvorlsy piece. Often such holes must bedriven.with-considerable accuracy las to location and alignment, and it`is frequently necessary to employ a jig rixedly locatedwitherespectfitothe'work piece, and havingflocating `holesxforthe`secureirlentand support of the motor-'driven rdrillinpr'operqnositionand alignment, yet still it is desirable to Vemploy the:same drill, without the necessity'ofr'ecourse 4to.fa,special:tool. Anexample of such tools andtheir support isfound in the patents torI`=aylor,No. 2,541,306,dated February 13, 1951, and No. 2,488,992,datedNovember 22,;1949.v

The Taylor patentsjdisclose afdrilling tool which is capable of Vbeingsupported upon a jig,fin:.X:ed alignment with a locatinghole, while amotor-driven drill `bit drills the `work piece, but thel1'1`aylor1toolis objectionable in that it is a'special-punpose tool,not adapted gior-most drilling operations, but only. in conjunction,.with such ,rfa lt is further -objectionablefin that,lbeing heavy andintended for support `whollybyme-ans-ofcornplemental two-part couplings,ofwhich one part-isacarried'atthe tip of the tool body-and-theL-otherpart is=iix,edin.the locating hole, the couplings must be`don-genough to afford reasonable assurance of-support for .thecantilevered weight, irl` Correctalignment.. The ,jig-mounted couplingpart or bushing is necessarily of Vsuchdength that -it projectsmaterially .from its locatinghole `infthe jig. The heavy weight of thetool,otherwise unsupported, and its vibration, soon create inaccuracies.in alignment. Moreover, Vthe lprojection of Athe. bushings yfrom .thejig, necessary as it is to afford :propersupport and .alignment, leavevthem where .they Vare .not'infr'equently struck accidentally, and so the.bushing is moved .lfrom ,alignment, or is loosened. Theinterengagingsurfacesy of the bushing and of the :motor-supporting frameArr'i'ustffitfvery accurately, yet .they are subject to -wear beeauseof.the

, large forces applied .to the small surfaces. Iheprojecting bushingsare a source` of possible injury to workmen and of damage to `theworkmans clothing. lt rvhas been found in practice that suchprojecting'ttings have been SiC.

The tool ofv the present inventionis designed 'for use with an ordinarymotor-driven drill, for attachment thereto and detachment therefrom.vThe drill, therefore, can be used asan ordinary` portabledrilhfhandheldand the source of much ,damage,lmisalignment,, annoyance,

directed, or by the securement to it of a small framethe same drill canbe supported .upon a jig .with great accuracy. All parts necessaryforthe support and alignment ofthe drill are mounted inthe separateframe; in small compass, and only this small and relativelyinexpensiveseparate assembly need be 'suppliedto 4enable the ordinary-drill toaccomplish extremely accurate, jigguided work, in additionto its normallwork. lIn addition, the mann-er of support ofthe tool and its 'attachedframe upon the jig is such thatno projecting bushings are required inthev jig, and no accurately interfitting surfaces of complementalcoupling parts are required, yet

c 2,839,953 Patented Y J une 24, 1195-8 rice the' tool can be heldaccurately, and'over a longer useful life, 'than with' the -mountlof theprior type. -"1`he'eli11`ina tion of projecting-'bushings avoidsaccidental misalignment thereof, andf'injuriesto `.workmen fand damageto their clothing. I i" More specifically, it is anlobje'ct toaccomplishthe support of such aV drilllmotortrom -ajigby rrneans of 'anexpansible andcontractible'colleg 'mounted in aiseparate frame attachedimmovably'to-the drill 'rnotor,"together with meansfor expanding 'andso'iixing the kcollet `within the locating hole,'or converselyfor'c'ontracting .itifor movement into and from the hole. Moreover,itis'fa further object to provide convenient means `'for accom'-plishing this expansionfandfcontraction 'of the 'colletgand fory holdingthe samein Ianygiven position "against the possibility of accidentalfc'ontraction. 'The'weight ofthe tool Ais braced "from the jig,@outwardly 'of theloca'ting hole, relieVin'gthebushing therein 'of ialarge part "of the matically correct 'alignment of therdrillfs axis'duringfth'e process of expanding the Vcollet 'within'th'e locatingVhole,

and will constitute abraceFwhich -relieves the collet 'and its h'ole-from the moments which, in `previous devices, Vdeformed theAinterengage'dcouplingiparts. f

With'such objects 'in irnind, an'dfothers as willfappe'ar more LVfullyhereinafter, -the .present :invention comprises the novel drillmotor-supporting means, shown -in' 4a typical for-m in 'the accompanyingdrawings, `and the principles -whereof will'be more yfully` explainedherein- 'after and defined by the claims. 1

`Figure 1 is an isometric view of the supporting'means in Iassociationwith the dril1,'but .with the mo'tor'frame only-indicated in dot-dashlines, and showing 'by dotdash lines, by vdas-h lines, and in fulllines, respectively, three different positions of the operating handle."

Figure 2 isa viewlto an enlarged scale, similar vtoFigure 1, but withparts broken away and shown in section or in phantom, and illustratingva diierent positionof the operating handle. i

ZFigure 3 is'aii axial sectional "viewof the supporting means inposition ready toenter a locating hle ofa jig, 'and'FigureA isa similarview'withthe supportingfm'eans body is indicated vat M in Figure 1, andthe drill rotated 'thereby is indicated at D. The/jig is indicated at fJwith aY locating hole L supported'in accurate position with respect-,toVa work piece W. The locating hole L 'may desirably mount a -reverselytapered bushing B, not only because the reverse taper is of advantag'einthe securement of the supporting means in place, but also as a means tominimize the effects of wear, for the 'bushing B may beef hardermaterial thany the jig. The'manne'r in which the bushing is secured inplace in the Vlocating hole L is immaterial. -it is intended tobe'mounted permanently in place therein, and in rparticular -itfv'vill benoted that the Ybushing/'B does not project from 'either surface of thejig J. 'l p.

A frame 9 of generally tubularshape `is suitably` formed and arranged atone end, asfor example by the provision of threads 9u, for itssecurement to the tool body M.

. of :the collet. manner to grip the interior `of 'the 'locating hole Lorl of the reversely tapered bushing B, and in addition to tending totighten or grip thecollet Lwithin the locating'hole,

When secured together',- the two are relativelyimmovable.l 'Iheframe9.may be provided with access openingsand lightening holes asshown,.,but these are primarily for convenience, and need not bedescribed in detail. Atv its end `opposite the. securing means 90, thetubular frame 9 is .substantially continuous, although itis open at itsend,. and .is provided with acircumferentially directed slot 91, whichextends, `in the form shown,` through substantially 180.

Supported from the frame 9 coaxially ofthe drill D and .surrounding .thelatter, at least when the drill is retracted as at the commencementofa`drilling operation, is a t guide sleeve 2. This -guide sleeve is Vfixedwith relatin to the frame 9, for example, by means of pins 20 by whichit issecured to a threaded sleeve or bushing21, which is threaded withinthe; frame 9, and which -may be heldin place by a set screw 22.yInteriorly, the guide sleeveis of a size to passtthe `drill D.

`Guided upon theV guidesleeve 2 for relative axial movement is anexpansible andcontractiblel collet, designated generally by thenumeral 1. The separable resilient fingers 11 thereof are of a size:externally to enter the locating hole Lor its bushing IB when thecollet is contracted, but to grip the ,bore of the bushing when the a xcollet fingers are expanded.. .The continuously circular portion 12 ofthe colletv is pinned tov a sleeve 14,A which at its inner end isthreaded, as indicated at 15; preferably the threads are of :fairly highpitch, say of 7 slope,

hence are inherently self-locking in a givenposition Vof ez adjustment-The collet -1 with its threaded sleeve 14 constitute, in effect, asingle.continuous sleeve, which is guided upon the guide-)sleeve 2 for.relative axialmovement. :Provision is made for preventingrotationalmovement of this sub-assembly; for instance, a key projectingfrom a retainer 18 isrcceived in a keyway 17 extending `lengthwise of`the sleeve y14.A Theretainer 18 is fixed to theframe 9 by a scre w 19.'A nut 3 has .internalI threads complementallyiengagsequently-the colletl, on theone hand, and the nut3 on the other hand, will be effected.Such rotational` move- -ing the threadsJS,v of the sleeve Y1 4, sothatby Arotation .2.a

ment may .be-accomplished by any suitable means, such, it.;

for instance, as'the handle 31, carried by the nut 3, and

projectingmore or lessradially therefrom through the slot `91.

s An indexring assembly 4 is supported from the frame,

disposed coaxially of `the collet and guide sleeve inter-Y`l` mediatethe jig J and the left-handrface of the nut4 3.

A thrust bearing 41 is interposed therebetween. Assuming the collet tobeengaged within its bushing B, rotation of the nut 3 in one rotative.sense urges theindex ring 4 against the face of the jig and Abyreactiorx'urges; theJ collet 1A to theright.Y The collet and the guidesleeve 2, t

which is tixedjwith relation to the frame, `are provided .at theirrespective Atips with cooperating cam surfaces 16 `and 26, which,uponsuch relativeaxialA movement of the M collet and guide sleeveggcauseexpansion ofthe fingers 11 This, of course, expands the collet ina byreaction from the now-gripping collet, Vit tends also to draw `theentire frame and Athe tool supported thereby towardithe jig J.-Preferably, .a resiliently depressiblc Contact ring 42 ofarrubber-likematerial is interposed between the index ring 4 and the`facing surface of the jig. When theframe is drawn to the left, this:conta'cti in order to align itl axially-.within the hole or. the bush-Ito bear at 93 again'stthe frame), and so effects reverse .also in dashlines in Figure 3, the `collet is readily inserted within or removedfrom a bushing B.

SinceV rotation ofthe nut 3 Yand its operating handle 31 serves toaccomplish relative movement of the guide sleeve 2 and the collet'l, itis desirable to provide means for' retaining the nut in any givenposition of rotative adjustment, at least, within a given range. Thismay be accomplished by the provision of a dog 33, on the handle 31, andan arcuate rack 94 on the frame 9, interengageable to the' endindicated.Y A spring 34 and flexible wire release 35 serve to retain thedetent in engagement with the rack, or to release the same,respectively.y Y

When it is desired to locate the motor M and the drill D in operativeposition with respect to the work W, the collapsed tip of collet lisentered within the proper locating hole L, which usually will beprovided with the reversely tapered bushing B, or otherwise will beitself reversely tapered. Parts are shown in full lines in Figure 3 inposition for entrance into the bushing B, and in dash lines, the tip ofthe collet has been shown entered Within the locating hole. With partsin the latter position, the nut 3 is rotated from a position such as thefull line position of Figure 1 to the dot-dash line position of thelatter figure, orv into the full line position of Figure 4. This effectsrelative axial movement between the collet and the guide sleeve 2, andexpands the tip of the collet into locating engagement with the bushingB. In order to effect this, the relative axial movement between the nut3 and the threads 15 produce a reaction, bearing at 41 and so urging theindex ring 4 against the jig J. The initial reaction `of the jig urgesthe collet 1 to the left andthe guide sleeve 2 correspondingly to theright, so that'the collet is expanded into locating engagement with- `inthe locating hole and the bushing B. This position of parts is shown inFigure 4. Continuing the relative rotation of the nut and the threadsl5, the same reaction continues, but 'now the resistance of the parts toappreciable Ysecuresupport or bracing for the same. The motor is thenenergized, and by means not shown herein, but described'in the Taylorpatents, the drill is urged forwardly intoV and through the work piece,after which the drill is retracted, and by reverse rotation of the nutrelative to the threads '15, the reaction now taking place between thenut and the face 93, the guide sleeve 2 is withdrawn Withinthe collet 1,the cam elements 26 and 16 again rre-engage in their relaxed position,and the collet fingers contract. The device may now be removed bodilyfrom the jig, 'and is ready to re-engage immediately within the nextlocating hole.

I claim as my invention:

1.'In combination `with a portable drillor like tool which includes atool body and a tool bit movable axially of thetool body, a jig havinglocating holes and capable of being exactly positioned with relation toa workpiece to be drilled, a frame means for securing said frame to thetools body, an expansible collet supported and project-ing from an endof said frame,` surrounding and coaxial with the tool bit, and of a sizewhen contracted to enter a locating ing B. The large diameter index ringrelievesl the bush ,v

ing lB of any moment, and braces the entire tool from the circle ofcontact. Reverse rotation of the nut3 causes it 75 hole of the jig,` andmeans reacting between said collet and said frame for expanding thecollet into coaxial engagement with the walls of such hole, when enteredthereinto, to support and locate the frame, the tool body, and the toolbit, with relation to the jig and so with relation to the workpiece, andfor contracting the collet for removal of the tool from the jig.

2. A device as in claim 1, wherein the collet-expanding means includes athreaded sleeve coaxial with and fixed to the collet, a nut threadedupon said sleeve and i bearing axially against the frame, a guide sleevexed to the frame, coaxial with the collet, and means to rotate said nutto shift said threaded sleeve and collet axially relative to said guidesleeve, and complemental cam surfaces upon said guide sleeve and saidcollet positioned for interengagement to expand and to permitcontraction of the collet upon their relative axial movement inrespectively opposite senses.

3. The combination of claim l, including additionally bracing meanscarried by the frame and positioned for engagement with the face of thejig radially outwardly of the locating hole wherein the collet isengaged, to brace the frame and the tool body secured thereto when thecollet is so engaged.

4. In combination with a portable drill or like tool which includes atool body and a tool bit movable axially of the body, a jig havinglocating holes and capable of being exactly positioned with relation toa workpiece to be drilled, a frame, means for securing said frame to thetools body, and supporting the latter for relative movement of the toolbit in the axial direction, an expansible collet surrounding and coaxialwith the tool bit, and supported and projecting from an end of saidframe for axial movement, and said collet being of a size whencontracted to enter a locating hole of the jig, means reacting betweenthe collet and the frame for shifting the collet axially, an index ringxedly mounted upon the frame coaxially of the collet, in positionadjacent the face of the jig when the collet is entered into a locatinghole, and means reacting between the collet and the frame, and operableby their relative axial movement, to expand the collet into engagementwith the walls of such hole, and to draw the index ring into engagementwith the face of the jig.

5. In combination with a portable drill or like tool which includes atool body and a tool bit movable axially of said body, a jig havinglocating holes and capable of being exactly positioned with relation toa workpiece to be drilled, a frame, means for securing said frame to thetools body, and supporting the latter for relative movement of the toolbit in the axial direction, an expansible collet surrounding and coaxialwith the tool bit, and supported and projecting from an end of saidframe for axial movement, and said collet being of a size whencontracted to enter a locating hole of the jig, a threaded sleeve guidedin the frame for axial movement, and fixed to said collet, a nutthreaded upon said threaded sleeve and guided in the frame for rotarymovement only, means to rotate said nut, thereby to shift said colletaxially, and means reacting between the collet and the frame, andoperable by their relative axial movement, to expand the collet intoengagement with the walls of such a hole, for supporting engagement ofthe frame and tool with the jig.

6. Supporting means as in claim 5, including additionally an index ringlixed to the frame, whereby the 7. Supporting means as in claim 6,including a resiliently depressible mount ring carried by said indexring and bearing upon the jig.

8. The combination of claim 5, wherein the colletexpanding meanscomprises complemental cam means upon the collet and upon a member ofthe frame, interengageable by axial movement of the collet to expand thelatter.

9. The combination of claim 5, wherein the colletexpanding meanscomprises a guide sleeve fixed to the frame and disposed within andguiding the collet, and complementa] cam means formed upon the colletand upon said guide sleeve, interengageable by axial movement ofthecollet to expand the latter.

10. Means for supporting a motor-driven drill or like tool, whichincludes a tool body, removably upon a jig xed with relation to aworkpiece, vand such as has locating holes, said supporting meanscomprising a frame separate from and arranged for securement immovablywith respect to the tool body, a guide sleeve coaxial with the drill andfixed to the frame in projecting position surrounding the drill, anexpansible collet slidably supported upon said guide sleeve, of a tipsize to enter the locating hole when contracted and to grip the interiorwalls thereof when expanded, the collet `and the guide sleeve havingcomplemental cam surfaces cooperating to expand the collet by theirrelative movement in one axial sense, and vice versa, an externallythreaded sleeve xed to the collet and axiallyguided upon said guidesleeve, a nut threaded upon said threaded sleeve, an index ring mountedupon said frame and bearing at one face upon said nut, and positioned tobear at its opposite face upon the jig when the collet is entered withina locating hole, said nut bearing -at its opposite face upon the frame,and means to rotate said nut for expansion and contraction of thecollet, and for urging the index ring against the jig.

11. A coupling and supporting device for a tool body wherein a tool bitis guided and supported for feeding and retracting movements along thetools axis, said device comprising a frame separate from and formed forsecurement to the tool body, surrounding the tool bit, a jig havinglocating holes and capable of being exactly positioned with relation to4a workpiece, a bushing disposed substantially wholly within each suchhole, coaxial therewith, an expansible collet supported by andprojecting from said frame, surrounding the tool bit and coaxial colletis axially slidably mounted with respect to said index ring, said indexring being positioned to bear at its one face against the jig when thecollet is received within the locating hole thereof, and shifts axiallyrelative to the frame.

with the same, and guided for axial sliding movement relative to theframe, said collet when retracted being of a size to enter a bushing inthe ji'g, means reacting between the frame and said collet for electingrelative axial movement thereof, and means interengageable by suchrelative axial movement for expanding the collet into supportingengagement with the walls of such bushing, and coaxial therewith, andfor contracting the collet for removal of the tool, and an index ringcarried by the frame, spaced radially outwardly from the collet, inposition to engage the face of the jig, as a brace, upon expansion andaccompanying axial movement of the collet.

1,630,083 2,669,887 Rees Feb. 23, 1954 2,706,917 Hill Apr. 26, 1955

